Electronic sensor arrays are finding increased use for detecting analytes in fluids, such as gases or liquids. In particular, arrays of sensors based on field effect transistors are finding use in detecting ionic components, such as various cations, anions or pH. Such sensors are often referred to as ion-sensitive field effect transistors or ISFETs.
Recently, such sensor arrays have found use in sequencing polynucleotides. Nucleotide addition results in the release of ionic species that influence the pH in a local environment. Sensors of the sensor arrays are used to detect changes in pH in the local environment resulting from the nucleotide addition. However, the pH of the local environment can be influenced by the interaction of various materials with hydrogen ions, leading to lower accuracy and less sensitivity to changes caused by nucleotide addition.
As such, an improved sensor array would be desirable.